A moving vehicle constantly is being decelerated by the air resistance acting thereon. Thus, in order to overcome this constant deceleration the vehicle constantly consumes energy. There have been attempts to use the air resistance acting on a vehicle for actively decelerating the vehicle or for transforming the energy of the air stream passing the moving vehicle into a usable form of energy that can be stored and used by the vehicle.
For instance, WO 2006/024208 discloses an aerodynamic auxiliary braking apparatus for a motor vehicle. The roof of the vehicle is configured as a main air resistance plate. The plate is hinged to a corresponding part of the vehicle body.
Concerning the transformation into a useable form of energy U.S. Pat. No. 4,254,843 discloses an electrically powered vehicle having a bank of batteries supplying electricity to an electric motor driving wheels of the vehicle including a whirl ventilator system, a clutch system and an automatically operated, engine-generator unit for recharging the batteries. The whirl ventilator system includes housings to produce a whirling air flow rotating a fan to drive an alternator such that air flow from movement of the vehicle generates electricity to charge the batteries. The clutch system includes a clutch mechanism coupling a drive shaft and a driven shaft to impart a driving force to the wheels when the drive shaft is rotated faster than the driven shaft and to couple the driven shaft with a flywheel when the driven shaft is rotating faster than the drive shaft, the flywheel driving an alternator such that momentum of the vehicle causes the alternator to charge the batteries. The automatically operated, engine-generator unit is started to charge the batteries when the level of charge therein has dropped below a predetermined level and stopped when the charge level reaches a second predetermined level.
U.S. Pat. No. 5,280,827 discloses an electric motor-driven vehicle having a large wind turbine mounted at the rear of the vehicle that rotates about an axis perpendicular to the axis of the vehicle body. A long venturi tube extends along the upper portion of the vehicle above the passenger cab and directs air flow from the front of the vehicle and impinges it upon an upper portion of the turbine blades. A pair of elongated lower screw-type turbines are contained in separate lower venturi effect tubes extending along the lower side of the vehicle below the passenger cab. Air from the lower venturi effect tubes is impinged upon the large turbine in a direction and at a location to increase the force generated from the upper venturi tube. The turbines drive one or more electric power generators coupled to storage batteries for recharging the batteries.
U.S. Pat. No. 5,386,146 discloses an in-line fluid medium driven charging system including a fluid medium driven generator disposed in a fluid medium directing tube. The fluid medium driven generator includes an auger shaped, fluid medium engaging member and is coupled to an electrical generator. Rotation of the auger shaped, fluid medium engaging member by intercepting a flow of a fluid medium causes rotation of the electrical generator, thereby generating electrical energy which recharges and assists in maintaining the life of a battery in a moving vehicle.